Development of penetrating projectiles as currently used in anti-armor applications has addressed numerous technological difficulties in order to produce effective weapons. The basic requirements of a long-rod penetrator includes the use of high density projectiles having a long length-to-diameter ratio and having very high impact velocities. The presently available projectiles are generally used for maximum target penetration of a hardened structure. The invention adapts long-rod penetrators with the capability of traveling both in air and water where the object is to achieve low-drag water penetration for the purpose of delivering high kinetic energy to underwater targets. This requires that the hydroballistic projectile maintain stability and low drag both in air and water so that sufficient kinetic energy can be delivered to the underwater target to assure its destruction.
Current projectiles do not exhibit the capability to travel in both air and water and deliver high kinetic energy to defeat targets at any significant depth below the water surface. An operational need exists for a projectile having the capability of launch above the water surface and providing effective water travel after impact with the water surface.